Flew it "baffleless" last weekend... difficult to say if there was any improvement since I had to do a fair amount of retuning (the motor is still breaking in, and the weather had changed drastically since the last flying session from cold & damp to very hot & dry), but I was able to get a little over 9000 RPM with a 14x12 APC. I wasn't able to get that before (more like 8800), so if there was an improvement it was minor...

Either way, I do like the sound better without the baffle... so off it stays. Thanks again for your help.